The present invention relates to an optical projection apparatus comprising, in this order, a light source, a liquid crystal display panel and a projection lens for projecting an image generated by said panel onto a projection screen.
Such apparatus is widely known, and FIG. 1 shows an embodiment of such apparatus. In a rectangular housing 1 are provided from the rear end to the front end, and along a projection axis 14 a lamp 6, a filter 5, a converging lens 4, a liquid crystal display panel 3 and a projection lens 2. The housing 1 is provided with air inlet holes 7 and 8 for inhaling coolant ambient air and with a fan 9 for exhausting this air. The directions of the air streams are indicated by arrows 12.
The projector housing is placed so as to have an inclination with respect to a surface 10 such as a table or the like by means of a stand 11 drawn by a dot line. Details of the stand 11 are not shown, but the upper end of the stand 11 is shifted in upward and downward direction, indicated by an arrow 13, by hand adjustment, which is a well-known technology.
It is difficult to make the conventional projector compact due to its construction. Furthermore a complicated angle adjustment mechanism for adjusting the inclination of the body is required in order to project an image onto a screen.